This project is designed to continue the assessment of the efficacy of extracorporeal immunoadsorption therapy in treatment of various models of rheumatic and neoplastic diseases in the dog which have now produced promising results. We have developed several immunoadsorbents to which immune reactants have been chemically conjugated or physically entrapped. Each of these immunoadsorbents has been tested extensively in vivo in an extracorporeal circulation system in normal dogs and now in canine hosts with naturally occurring models of human disease, namely systemic lupus erythematosus and adenocarcinoma of the breast. Canine glomerular basement membrane antigen (GBM) has been physically entrapped in a collodion-charcoal immunoadsorbent which has resulted in extraction of circulating GBM antibody and attenuation or arrest of passively induced nephrotoxic glomerulonephritis. Adsorption of circulating porcine specific canine antibodies by extracorporeal perfusion of canine plasma through procine kidneys has resulted in marked reduction of porcine specific antibodies and permitted the prolonged functional survival of a porcine renal Xenograft perfused with whole canine blood. Extracorporeal immunoadsorption over immobilized staphylococcus aureus-Cowans I has effected the removal of immune complexes and IgG in dogs with SLE. Similar perfusion of a dog with adenocarcinoma of the breast resulted in a marked gross and histologic regression of substanial tumor mass. C1q has been immobilized in collodion membranes and nylon wool and has demonstrated a capacity to extract immune complexes from the circulation of mongrel dogs. In addition, a chemotherapeutic program has been developed to effect the specific and sustained reduction of antibodies after extracorporeal immunoadsorption. We have now standardized several new radioimmunoassays to measure C1 binding, DNA binding and porcine-specific antibodies in the dog. The objective of the proposed experiments is to continue the longitudinal studies already begun of adenocarcinoma of the breast, SLE and heterotransplantation with our newly developed immunoadsorbents. These studies will involve careful serological and immunohistochemical assessment of the total disease process. Further studies are aimed at refining techniques for specific immunosuppression following extracorporeal immunoadsorption of pathogenic immune reactants and of improving methodology for whole blood (Text Truncated - Exceeds Capacity)